OVERVIEW

What is stress-induced hyperglycemia?

Severe physical trauma such as infections, injuries, massive bleeding, or major surgeries can trigger a series of chain reactions within the body, known as "stress." The phenomenon of elevated blood sugar levels under such stressful conditions is called "stress-induced hyperglycemia."

Stress-induced hyperglycemia can lead to many adverse outcomes for patients, often worsening the disease, delaying recovery, and largely indicating a severe condition with potentially poor prognosis.

Is stress-induced hyperglycemia common?

Stress-induced hyperglycemia occurs when the body experiences severe trauma, infections, or other stressful conditions, primarily affecting critically ill patients.

Among critically ill patients, the incidence of stress-induced hyperglycemia is approximately 43–50%, meaning nearly half of such patients may develop it. This shows it is highly prevalent in severe cases.

Is stress-induced hyperglycemia the same as diabetes?

No. The two conditions are distinct.

Stress-induced hyperglycemia arises after severe physical trauma or stress, is temporary and transient, and usually does not cause persistent high blood sugar, unlike diabetes.

It is worth noting that some patients may have undiagnosed diabetes or pre-diabetes (impaired glucose tolerance). Under stress, their blood sugar levels rise significantly, revealing the previously "hidden" diabetes.

Once the stress subsides, blood sugar may not fully normalize, and these patients may face long-term glucose management issues.

SYMPTOMS

What are the common manifestations of stress hyperglycemia?

Stress hyperglycemia is secondary to critical illness. The symptoms of hyperglycemia become negligible under these life-threatening conditions, and patients often primarily exhibit manifestations of these severe diseases. The symptoms of hyperglycemia are usually atypical, and stress hyperglycemia is often only detected during blood glucose monitoring.

What serious consequences can stress hyperglycemia cause?

If stress hyperglycemia is not properly managed, it can exacerbate the underlying disease, further worsening the condition. It may also hinder and delay recovery, while inducing various complications such as severe infections, polyneuropathy, multiple organ failure, and even death.

CAUSES

What are the common causes of stress-induced hyperglycemia?

Stress is the primary cause of stress-induced hyperglycemia. Stress can be categorized into exogenous and endogenous types.

• Exogenous stress mainly includes: acute trauma, burns, medical treatments (such as surgery, anesthesia, interventional therapy, dialysis, contrast imaging), extreme cold or heat, radiation injury, intense exercise, poisoning (toxic substances or drugs), infections, etc.

• Endogenous stress mainly includes: high fever, severe chest pain (e.g., caused by myocardial infarction), abdominal pain, hypoxia, difficulty breathing, suffocation, vomiting, diarrhea, acute bleeding, coma, convulsions, respiratory distress, cerebrovascular accidents, etc.

Who is more likely to experience stress-induced hyperglycemia?

Stress-induced hyperglycemia is commonly seen in critically ill patients.

Is stress-induced hyperglycemia contagious?

No.

Is stress-induced hyperglycemia hereditary?

No.

DIAGNOSIS

How is stress-induced hyperglycemia diagnosed?

When diagnosing stress-induced hyperglycemia, doctors primarily refer to the following criteria: the patient has no prior history of diabetes.

During stressful conditions such as severe infection, trauma, major surgery, or critical illness, venous blood glucose is measured two or more times. A fasting blood glucose level ≥ 7.0 mmol/L (126 mg/dl) or a random blood glucose level ≥ 11.1 mmol/L (200 mg/dl) confirms the diagnosis of stress-induced hyperglycemia.

What tests are needed when stress-induced hyperglycemia is suspected?

Generally, blood tests are required, including venous blood glucose, glycated hemoglobin (HbA1c), and glycated serum protein (GSP).

• Venous blood glucose: Fasting or random blood glucose (measured at any time) is primarily used to determine the presence of hyperglycemia.

• Glycated hemoglobin (HbA1c): Reflects the average blood glucose levels over the past 2–3 months. Elevated levels indicate pre-existing diabetes.

• Glycated serum protein (GSP): Reflects the average blood glucose levels over the past 2–3 weeks. Elevated levels suggest recent high blood glucose levels.

How to differentiate between stress-induced hyperglycemia and diabetes?

Both stress-induced hyperglycemia and diabetes present with high blood glucose levels, making them easily confused. Doctors rely on indicators such as HbA1c and GSP for differentiation.

• If blood glucose, GSP, and HbA1c are elevated to a similar extent, it suggests pre-existing diabetes with poor glucose control over the past 2–3 months.

• If blood glucose is high, and the increase in HbA1c is greater than that of GSP, it indicates pre-existing diabetes with relatively good glucose control in the past half-month.

• If blood glucose is high, and the increase in GSP is greater than that of HbA1c, it suggests elevated blood glucose levels in the past half-month. If there is no prior history of diabetes, it may indicate early-stage diabetes.

• If blood glucose is high, but both HbA1c and GSP are normal, it suggests stress-induced hyperglycemia or glucose infusion during blood sampling.

However, some patients with diabetes or prediabetes may have normal HbA1c and GSP levels, making it difficult to distinguish from stress-induced hyperglycemia.

In such cases, an oral glucose tolerance test (OGTT) can be performed 2–4 weeks after the stress is resolved for further clarification.

TREATMENT

Which department should I visit for stress-induced hyperglycemia?

Endocrinology or Critical Care Medicine. Patients with stress-induced hyperglycemia are usually in critical condition and often stay in the Intensive Care Unit (ICU). An endocrinologist may be consulted to assist with treatment.

Can stress-induced hyperglycemia resolve on its own?

Stress-induced hyperglycemia is temporary and typically resolves once the body's stress state is alleviated. However, if the patient previously had undiagnosed diabetes, blood sugar levels may remain elevated even after the stress is relieved.

How is stress-induced hyperglycemia treated?

1. Aggressively treat the underlying critical illness causing elevated blood sugar, such as trauma, infection, cardiopulmonary dysfunction, or cardiovascular diseases. 2. Provide nutritional support with appropriate calories and protein. Doctors will decide between enteral or parenteral nutrition based on the patient's ability to eat. 3. Use insulin to lower blood sugar as needed. Most patients are not suitable for oral hypoglycemic drugs.

What should the target blood sugar range be for stress-induced hyperglycemia patients?

For critically ill patients (e.g., those in the ICU), doctors often use intravenous insulin to maintain blood sugar levels between 7.8–10.0 mmol/L. For non-critical patients, subcutaneous insulin injections can be used, aiming for fasting blood sugar below 7.8 mmol/L and random blood sugar below 10.0 mmol/L, provided hypoglycemia does not occur.

Do stress-induced hyperglycemia patients require hospitalization?

Yes, hospitalization is necessary because these patients are often in critical condition and may even require ICU treatment.

What are the common side effects of treatment for stress-induced hyperglycemia?

Most patients with stress-induced hyperglycemia are not suitable for oral hypoglycemic drugs and require insulin to stabilize blood sugar. The main side effect of insulin therapy is severe hypoglycemia, which—or alternating episodes of hyper- and hypoglycemia—can hinder recovery and even be life-threatening. Insulin analogs are preferred over recombinant human insulin as they reduce the risk of hypoglycemia.

Can stress-induced hyperglycemia be completely cured?

If the patient had no prior history of diabetes or impaired glucose tolerance, stress-induced hyperglycemia can usually be fully resolved once the stress state is alleviated.

DIET & LIFESTYLE

What should patients with stress hyperglycemia pay attention to in their diet?

It depends on the specific cause of stress hyperglycemia.

Does stress hyperglycemia require follow-up testing? How is it done?

To further determine whether the patient has diabetes or stress hyperglycemia, a follow-up test is required 2–4 weeks after the stress condition is resolved. The main follow-up test is the oral glucose tolerance test (OGTT).

The specific procedure is as follows: Blood is drawn in the morning on an empty stomach to measure fasting blood glucose. Then, the patient drinks 300 ml of water containing 75 grams of glucose (the hospital will prepare this). Timing starts with the first sip, and blood is drawn again after 2 hours to check the 2-hour post-glucose blood sugar level.

Avoid strenuous exercise and eating during these 2 hours. If thirsty, a small amount of water can be consumed.

Does stress hyperglycemia affect fertility?

Stress hyperglycemia is temporary and transient. After recovery, it does not affect fertility.

PREVENTION

Can stress-induced hyperglycemia be prevented?

There is currently no effective prevention method.